Restore (if migration to multi-master failed)

In case you failed to upgrade to multi-master you will need to restore from the backup you have taken previously.

Take extra care becase kops will not start etcd and etcd-events with the same ID on an/or for example but will mix them (ex: etcd-b and etcd-events-c on & etcd-c and etcd-events-b on ); this can be double checked in Route53 where kops will create DNS records for your services.

If your 2nd spinned master failed and cluster becomes inconsistent edit the coresponding kops master instancegroup and switch MinSize and MaxSize to “0” and run an update on your cluster.

Next ssh into your primary master:

systemctl stop kubeletsystemctl stop protokube

Reinitialize the etcd instances:

In both /etc/kubernetes/manifests/etcd-events.manifest and /etc/kubernetes/manifests/etcd.manifest, add the ETCD_FORCE_NEW_CLUSTER variable with value 1.

Delete the containers and the data directories while restoring also from previous backup:

Everyone knows what Kubernetes is, most of us know how to expose a service in NodePort, ClusterIP or LoadBalancer mode but not everyone knows how to use Ingress.

What is an Ingress Controller? In short it is a Load Balancer.

Why do we need it? For more control of you exposed services and not last, cost related; I’ll give an example here: If you are using 100 services exposed via ELBs on Amazon it will cost you around 2,000$/month but if you use one replicated Ingress Controller and expose the 100 services via it it will cost you only 20$/month.